[WIP]: allow deploy portia spiders  with scrapyd-deploy
fix w3lib deprecation warnings
update README doc for deployment with scrapyd
Merge pull request #90 from tpeng/scrapyd-support

allow deploying portia projects to scrapyd or Scrapinghub
Merge pull request #91 from tpeng/fix-w3lib-warnings

fix w3lib deprecation warnings